Cruiser and Road
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class of vehicle will be unaccustomed to. Also the 34-tonne model is competitively priced — its retail price is about £500 less than many equivalent imported vehicles.
But in the pure 32-ton class, the opposite is true, with Cruiser's price tag being £1,000 more than much of the corn petition. Much depends on what you compare Cruiser with, and care should be exercised because it is all too easy to find you are not comparing "apples with apples".
In fact the only mechanical difference between a 34-tonne and a 32-ton Cruiser is the gearbox — both Fuller nine-speed models, but 950 lbft rated in the former and 600 lbft rated in the latter. The bigger gearbox adds about 100 kg (220 lb) to the tractive unit's unladen weight.
There are also slight differences between the ratios of the two gearboxes. All Cruiser models use the 11.1-litre TL11 engine with an A-suffix for the two heavier models and a D-suffix for the 28-tanner to denote that governed engine speed is reduced to 2,000rpm from 2,200rpm for this 16.18 model.
Installed in the 16.21, the modestly turbocharged engine, developed from the well-known 680-Series, is rated at 156kW (209bhp) at 2,200rpm giving it a power to weight ratio of only 4.6kW/tonne (6.24bhp/ton) at 34 tonnes.
Like Leyland's engineers, I wondered if this power output would be enough for the toughest sections of CM's route, remembering also that in these days of high torque, Rolls-Royce and Cummins engines, the 820Nm (605 lbft) of the TL11A was not especially impressive (but in the pure 32-tonner class the Cruiser's maximum torque figure is greater than any of the competition).
The Cruiser didn't exactly fly over every hill, but never was it in any difficulty, even between Rochester and Neville's Cross where deceptive suddenly steepening gradients lie in wait to trap the unwary driver or underpowered vehicles.
On the very steepest hills the best technique was to get into first (not crawler) a little earlier than was absolutely necessary and then change rapidly into second as soon as the gradient allowed. Once the oil in the Fuller gearbox was warmed up this change of ratios, or indeed any other, could be made very quickly.
I suspect that if the Cruiser had been fitted with a synchromesh box rather than a constant mesh, the inevitably slower change would have made the modest power to weight ratio more noticeable.
But that's guesswork and if the Cruiser test at 34-tonnes proved. anything it was that preconceived ideas about the necessity of massive power to weightj ratios can be inaccurate.
Over the gentler 40mph sections of the route, the Cruiser's fuel consumption edged ahead of its more heavily laden running mate and the 34-tonner was just about able to hold its own on average speed.
But motorway sections were another story. Here the 28 tonnes of semi-trailer and payload and the wind resistance of the Crane Fruehauf van had much more of an effect on the lower-powered tractive unit and fuel consumption and journey times suffered.
Heavy throttle spring It was noticeable on motorway sections that the Cruiser had to struggle a bit to reach 60mph and hold that speed. Eaton's thermostatically controlled viscous fan cut in most often during motorway running, an indication that the engine was having to work hardest under these conditions.
A strong throttle return spring made it difficult to hold the pedal against its stop and could irritate a driver on a long run, and the heavy clutch action could be : source of irritation on urban de livery work.
These criticisms may seen minor, but they may not be t( the driver who has to spen( much of his working life in thl cab.
So why choose purely hy draulic operation? Leylam couldn't find a servo unit whicl satisfied its stringent durabilit, requirements, and its engineer: were probably right in thinkinl that most operators an prepared to sacrifice light clutcl operation in the interests of stay ing power. As for the throttle well that's simply a matter o fitting a lighter return spring, suppose.
Close temperature control The fan may have cut in mon often than expected or motorway sections, but th( noise was only just detectable certainly more subdued than th( whoosh of Roadtrain's Dynai fan.
Temperature control on th( Cruiser could not have beer lore effective. The needle limbed at about normal pace when starting from cold, but mce it had reached the halfway iosition on the dial, calibrated rum 60C to 130C, nothing would nduce it to move further — not !yen my furtive tapping on the lialface when Leyland per;onnel weren't looking.
It remained rock steady even m Carter Bar, Shap and in Edin)urgh's heavy traffic. And renember the tractive unit was aulling 34 tonnes, not 32.
.ow noise, good ride At a steady 50mph in top gear ve measured 75.5 to 76.5 dB(A) the driver's ear, and while we ;ouldn't take measurements at 30mph at MIRA because the :ruiser would not pull at that ;peed on the proving ground rack, we reached 60mph on the V16 and noise increased very ittle.
There were no annoying .attles or squeaks and even the .xhaust note and engine tone were subdued — much "softer" or example than the harshersounding Cummins 14-litre en)ines.
If a passenger in our test :wiser had been blindfolded he )robably wouldn't have known Ie was in a 34-tonner working at ts design weight rather than a 38-tonner working at 32 tons.
Tested at 32 tons, Roadtrain ;uffered cab nod and I expected he Cruiser, with a shorter wheelbase (2.884m) and a ;impler cab mounting system, would be worse.
Despite favourable first impressions, I reserved judgment an the ride until after the 01/4914/A91 section of CM's route, The variety of road surfaces on his section usually shows up
any shortcomings in suspension, but our 34-tonner was not found wanting. The ride was firm, but never uncomfortably so.
Without using test equipment, such as an accelerometer, it was impossible to tell which part of the suspension package was working hardest to insulate the driver from road shocks, but the "seat of the pants" impression was that it was the Chapman Bremshey suspension seat, though it never reached the limits of its stroke.
Unlike Roadtrain, with its two quarter elliptic springs support ing the rear of the cab, the Cruiser cab has two rear rubber blocks in shear, aided by two telescopic shock absorbers.
The Cam Gears power assisted steering may be a little heavier than normal these days, but whereas with Roadtrain I found that it was easy to seesaw around the straight-ahead position, the Cruiser seemed to have a better self-centring action and was more stable in the straight-ahead position.
If there had been any mismatching of transmission components in the Cruiser's clri veline, you can bet that a test at 34-tonnes gew would highlight it. I suspected that like the 290 Rolls-powered Foden at 40 tonnes we tested last year the Leyland's nine gear ratios would be too few at 34 tonnes.
But on level ground the Cruiser would move off with no trouble in second (third if you count crawler as first) and usually the next ratio could be skipped, using fourth and all the ratios in high range.
Our test vehicle was fitted with the lowest available ratio of 5.524:1 in the Guy hub reduction range, yet it restarted with ease on a one in five gradient. Had it not been for an engine misfire on the one in four test hill, a restart would probably have been possible on that gradient too. It felt as if the fuel lift pump couldn't pump fuel at such a severe angle unfortunate when a good flow of fuel is just what's needed on such an incline.
Maximum geared speed of the Cruiser was 104km/h (65mph), which meant that the engine was spinning at 2,100rpm at 60mph and 1,400rprn at 40mph.
Perhaps the only question remaining unanswered is why the ten-speed spriitter Spicer box is not fitted to Cruiser, at least as an option. There were occasions on CM's 750-mile test route when it would have been useful, if not essential. The light weight of the Spicer gearbox could be an important advantage for operators of 28 to 34 tonne tractive units, too.
Especially when the oil in the gearbox was cold, there seened to be just too much metal in the RI-09509,A gearbox for the little TL11A engine. After all, this gearbox was designed for engines with torque ratings of up • to 950 Ibft.
The two most obvious external differences in appearance between Roadtrain and Cruiser are the absence of a grille in the front panel on the smaller unit and single headlight units in place of pairs. The smaller cab looks to me even more aesthetic than Roadtrain and, of course, the absence of the grille leaves more scope for signwriting.
Leyland says the C40 cab has a deliberately "non-aggressive" appearance. That may be but few would argue that it is now the most attractive and modernlooking cab on the market. I can't agree with Leyland that it is inconspicuous in "normal traffic
situations". Everywhere on OL test route, both Cruiser an Roadtrain attracted admirin glances.
Summary If operators are looking fc more power at 34 tonnes, or ir deed 32 tons, then Cruiser has lot to offer. A charge-cooled ye sion of the TL11A engine coul perhaps satisfy their need perfectly.
The reason for not extractin
more power from the 11-litr unit could be an understandabl reluctance to jeopardise in an way the potentially excellent di rability and reliability of Cruise Leyland had never suggeste that it has any plans to introduc charge-cooler but it must be
possibility.
That could be the one car that Leyland needs to come u trumps in the lightweight trai tive unit market. However, mai. no mistake, the Cruiser range E it stands represents a vel strong hand, continued overlet